Navigation system



FIG. 1 is a perspective view of an inventive navigation system.

FIG. 2 is a front view of the navigation system.

FIG. 3 is a first side view of the navigation system.

FIG. 4 is a second side view of the navigation system.

FIG. 5 is a top view of the navigation system.

FIG. 6 is a bottom view of the navigation system; and,

FIG. 7 is a rear view of the navigation system. 

I claim the ornamental design for a navigation system, as shown and described. 